This specification relates to assessing associative memory and judgment associated with a cognitive task, such as can be done based on results of a cognitive test that has been administered to a person.
Various techniques have been used to measure the cognitive function of a person. For example, the National Institute of Aging's Consortium to Establish a Registry of Alzheimer's Disease (CERAD) has developed a ten-word list as part of the Consortium's neuropsychological battery. The CERAD word list (CWL) test consists of three immediate-recall trials of a ten-word list, followed by an interference task lasting several minutes, and then a delayed-recall trial with or without a delayed-cued-recall trial. The CWL is usually scored by recording the number of words recalled in each of the four trials. A single cutoff score for the delayed-recall trial, with or without adjustment for demographic variables, is typically used to determine whether cognitive impairment exists for a given subject.
Some have proposed various improvements to the CWL. In addition, the CWL and the improvements thereof have been used to provide memory performance testing services, via the Internet, to clinicians in daily practice. Such services allow rapid testing of individual patients and reporting on the results of such testing. Previous reports for individual cognitive performance test results have included a statement of whether the patient has been found to be normal or to have cognitive impairment. Other reports have provided different result details, and other techniques for brain condition assessment have been described, which have included the use of triadic comparisons of items, (e.g., deciding which one of three animals is most different from the other two). For example, see U.S. Patent Pub. No. 2009-0313047, U.S. Patent Pub. No. 2009-0155754, and U.S. Patent Pub. No. 2013-0191153.
In addition, judgment is an executive function that involves attention, working memory, comparison, reasoning, and response selection. Executive function refers to a complex set of cognitive abilities used to perform tasks that involve one or more components of idea generation, reasoning, analysis, judgment, insight, synthesis of new ideas, decision making, planning, organization and execution. General brain processes are used to produce these executive functional abilities, and include attention, working memory, comparison (reasoning), response inhibition (eliminating irrelevant information), set-shifting (flexibility), development of new associations (discovery or concept formation), response selection or decision-making, task preparation, sequencing and execution. Judgment of semantic similarities or differences can be impaired by disorders disrupting inferior prefrontal cortex lobe function, including but not limited to Alzheimer's disease, Frontal temporal lobe disease, Lewy Body/Parkinson's disease, schizophrenia, multiple sclerosis, epilepsy, depression, and traumatic brain injury.
A variety of tests have been developed to measure components of executive function, including, but not limited to, the Stroop Color Interference test, the Wisconsin Card Sorting test, the Delis-Kaplan Frontal Systems battery, Symbol Digit Modalities Test, and many others. Because of the complex nature of executive function, the tasks that have been developed to measure it are also relatively complex to administer, interpret and score.